Heterogeneous Hemostatic Disorder Associated with IgA Monoclonal Gammopathy: A Case Series.

INTRODUCTION: Monoclonal gammopathy, or paraproteinemia, involves monoclonal immunoglobulins in the blood and ranges from benign monoclonal gammopathy of undetermined significance (MGUS) to malignant multiple myeloma. Hemostatic abnormalities affect 15-30% of cases but are often under-recognized. This study presents three cases of Immunoglobulin A (IgA) monoclonal gammopathy with hemostatic dysfunction to enhance understanding of its pathophysiology and clinical impact.

CASE PRESENTATION: This report presents a retrospective review of three patients with IgA monoclonal gammopathy at Changhua Christian Hospital, including two with lymphoplasmacytic lymphoma and one with plasma cell myeloma, each exhibiting hemostatic dysfunction. Despite the same underlying IgA monoclonal gammopathy, the etiologies, clinical presentations, and laboratory findings varied significantly among the patients. Two patients experienced clinically significant bleeding episodes associated with acquired von Willebrand syndrome (AvWS) and platelet dysfunction. Conversely, one patient exhibited multiple coagulation factor deficiencies and platelet dysfunction but did not have clinically significant bleeding episodes.

CONCLUSION: This case series highlights the diverse hemostatic manifestations of IgA monoclonal gammopathy, including AvWS, platelet dysfunction, and multiple clotting factor deficiencies. Despite having the same class of monoclonal protein, patients exhibited distinct clinical and laboratory findings, suggesting heterogeneous mechanisms of coagulation impairment. Awareness of these presentations in hematologic and immunologic practice is crucial for diagnosis and individualized management. Further research is needed to elucidate the molecular mechanisms underlying these hemostatic defects and develop targeted management strategies.